There are numerous methods and devices in use to ensure the integrity of packaged goods such as sterile medical packages, pharmaceuticals, or food. Moreover, numerous methods for testing the integrity of the packages are known, and relate directly to the packaging in which a product is housed. For example, testing of products packaged in non-flexible containers employ procedures which do not apply to testing of products in flexible containers. Furthermore, the majority of testing methods are destructive, and leave the tested flexible containers in non-serviceable condition.
Methods and devices for testing the integrity of seals on packages are known. One such method and device is the apparatus and process for inspecting sealed packages described in U.S. Pat. No. 6,105,419. The device provides an apparatus for inspecting sealed packages of product, and requires a conveyor belt for receiving the packages. An inspection belt contacts the packages and moves away from the conveyor belt a particular distance depending on whether the packages are properly sealed. When engaged by a package with a good seal, the inspection belt is moved a first distance which causes an indicator carried thereon to send a signal which prevents removal of the good package from the conveyor belt. However, when a leaky bag contacts the inspection belt, the inspection belt is moved a second distance which is insufficient to cause the indicator to send a signal. Consequently, the improperly sealed package is removed from the conveyor belt. The inspection belt may be mounted for linear or pivotal movement upon being contacted by the packages carried by the conveyor belt. In addition, a package engaging member can be used to press the packages prior to passing under the inspection belt to facilitate the discharge of air from leaky packages.
While the above method provides a method of testing seals on packages, the method requires a conveyer belt and the package engaging member may actually damage the package. Additionally, this method does not provide quantitative data regarding leakage.
Another method for leak testing and leak testing apparatus is described in U.S. Pat. No. 6,202,477. The device serves to leak test closed containers which are filled with a filling product containing at least one liquid component. The container is introduced in a test cavity which is evacuated at least down to vapor pressure of that liquid component. The pressure in the surrounding of the container and thus within test cavity is monitored. Monitoring is performed by a vacuum pressure sensor, whereas lowering pressure surrounding the container is performed by a vacuum pump. Leakage is detected by monitoring a pressure change in the surrounding of the container which is due to evaporation of liquid emerging from a leak and being evaporated in the low pressure surrounding.
While the above method and apparatus serve to leak test packages, the packages are already sealed on all sides. Additionally an extremely complex apparatus is necessary to perform the testing.
Furthermore, safety is an important issue in the operation of pneumatic devices. Because of the forces generated by many of the testing devices, it is essential to develop a test apparatus and method that assures that the operator's extremities, such as hands or fingers, do not become trapped within the testing apparatus.
What is needed in the art is a leak testing apparatus for packages that is non-destructive to the packages under test.
Furthermore, what is needed in the art is a leak testing apparatus that provides features that assure that the operator does not sustain injury while performing testing.